Spawn of the Comet Part 4

That night again, Jim Carter presented himself at the Wentworth home in Hartford, and again it was Joan who admitted him.

"Oh, Jimmy!" she murmured, as he took her in his arms. "We're all so proud of you!"

"I'm glad someone is," he said.

"But what a fearful risk you ran! If you hadn't been able to get your motor started--"

"Why think of unpleasant things?" he said with a smile.

Then they went into the library, where Professor Wentworth added his congratulations.

"But I'm afraid I didn't accomplish much," said Jim, explaining about the pictures.

"Let me see them," said the professor.

Jim handed them over.

For a moment or two Professor Wentworth examined them intently, holding them this way and that.

"They indeed appear to be extremely over-exposed," he admitted at length. "Your Fire Ants are doubtless radio-active to a high degree.

The results could not have been much worse had you tried to photograph the sun direct."

"I thought as much," said Carter, gloomily.

"But possibly the damage isn't irreparable. Suppose we try re-developing a few of these negatives."

He led the way to his study, which since the destruction of the observatory had been converted into a temporary laboratory.

Ten minutes later, Professor Wentworth had his re-developing bath ready in a porcelain basin and had plunged some of the negatives into it.

"This process is what photographers call intensification," he explained. "It consists chemically in the oxidation of a part of the silver of which the image is composed. I have here in solution uranium nitrate, plus pota.s.sium ferricyanide acidified with acetic acid. The latter salt, in the presence of the acid, is an oxidizing agent, and, when applied to the image, produces silver oxide, which with the excess of acetic acid forms silver acetate."

"Which is all so much Greek to me!" said Carter.

"At the same time, the ferricyanide is reduced to ferrocyanide," the professor went on, with a smile at Joan, "whereupon insoluble red uranium ferrocyanide is produced, and, while some of the silver, in being oxidized by this process, is rendered soluble and removed from the negative into the solution, it is replaced by the highly non-actinic and insoluble uranium compound."

The process was one quite familiar to photographers experienced in astronomical work, he explained. In fifteen minutes they should know what results they were getting.

But when fifteen minutes pa.s.sed and the negatives were still as black as ever, Jim's hope waned.

Not so Professor Wentworth's, however.

"There is a definite but slow reaction taking place," he said after a careful examination. "Either the over-exposure is even greater than I had suspected, or the actinic rays from your interesting subjects have formed a stubborn chemical union with the silver of the image. In the latter event, which is the theory I am going to work on, we must speed up the reaction and tear some of that excess silver off, if we're ever to see what is underneath."

"But how are you going to speed up the reaction?" asked Jim. "I thought that uranium was pretty strong stuff by itself."

"It is, but not as strong as this new substance we have in combination with the silver here. So I think I'll try a little electrolysis--or, in plain English, electro-plating."

As he spoke, the professor clipped a couple of platinum electrodes to the basin, one at each end. To the anode he attached one of the negatives, to the cathode a small piece of iron.

"Now then, we'll soon see."

He pa.s.sed a low current into the wires, through a rheostat, with startling results. There was a sudden foaming of the solution and a weird vapor rose from it, luminous, milky, faintly orange.

For a moment, all they could do was stare.

Then Professor Wentworth switched off the current and stepped toward the tank. Waving away that orange gas, he reached for the cathode and held it up. It was no longer iron, but silver, now.

"Plated, you see!" he exclaimed in triumph.

"Yes, but those fumes!" cried Jim. "Why, they were the same color as the--the Fire Ants, as you call them."

"I know." The professor was not as calm as he pretended. "We have released some of their actinic rays captured by the negative, in prying loose our excess silver. Later I shall repeat the process and capture some of that vapor for a.n.a.lysis. At present, let us have a look at the negative already treated."

He lifted the anode from the solution now, removed the negative, and held it up. A smile of satisfaction broke over his face, followed by a shudder.

"There you are, Jim! Have a look!"

Jim looked, with Joan peering over his shoulder, and his pulses tingled. It was a clear shot of that scattering half-circle of fiery termites, taken after he got away and swept back over them.

"Say, that's wonderful!" he exclaimed.

"Wonderful--but horrible!" echoed Joan.

"I'll admit they're not much on looks," laughed Carter. "But their homely maps are worth a lot to me--ten thousand dollars, in fact!"

He told her why, and what he proposed to do with the money, and Joan thought it a very good idea.

While this was taking place, Professor Wentworth was re-developing the rest of the negatives.

At last all had been salvaged, even those taken in the terrific heat over that weird gla.s.s city out there, and Jim was preparing to bear them back to Overton in triumph.

He had thanked the kindly professor from the bottom of his heart, had even told him something of what he had been telling Joan. There remained but to put one last question, then go.

"Summing it all up, what do you make of those nightmares?" he asked.

"Do you think they can be destroyed?"

Professor Wentworth did not reply at once.

"I can perhaps answer your question better when I have a.n.a.lyzed this specimen of gas," he said at length, holding up a test-tube in which swirled a quant.i.ty of that luminous, milky orange vapor. "But if you wish to quote me for publication, you may say that when I have learned the nature of it, I shall devote all my energies to combating the menace it const.i.tutes."

And that was the message Jim took back with him, but it was the pictures that interested the practical Overton most.